|
|
Thread Tools | Display Modes |
#1
|
|||
|
|||
GPS Units = Show road steepness?
Talking about GPS units on another thread reminded me of something else I wondered if they do. Does a bicycle GPS unit show you the steepness of roads? There's an area that I frequently ride where on road has short but very steep hills, another road a mile or so east of it has much more gradual hills whilst a third road to the west of the first one is a major highway that can be ridden with a bicycle. What I'm wondering is this: if someone unfamiliar with the area got there and used a GPS unit to show those three roads, would the GPS unit show them the different gradients of the roads? Or is that another function that they'd need to download or otherwise install?
Cheers |
Ads |
#2
|
|||
|
|||
GPS Units = Show road steepness?
Sir Ridesalot wrote:
Talking about GPS units on another thread reminded me of something else I wondered if they do. Does a bicycle GPS unit show you the steepness of roads? There's an area that I frequently ride where on road has short but very steep hills, another road a mile or so east of it has much more gradual hills whilst a third road to the west of the first one is a major highway that can be ridden with a bicycle. What I'm wondering is this: if someone unfamiliar with the area got there and used a GPS unit to show those three roads, would the GPS unit show them the different gradients of the roads? Or is that another function that they'd need to download or otherwise install? Cheers My Garmin 705 shows the slope as I ride it, and historically, but not preemptively. For that, I used Google Earth. |
#3
|
|||
|
|||
GPS Units = Show road steepness?
Sir Ridesalot wrote:
Talking about GPS units on another thread reminded me of something else I wondered if they do. Does a bicycle GPS unit show you the steepness of roads? There's an area that I frequently ride where on road has short but very steep hills, another road a mile or so east of it has much more gradual hills whilst a third road to the west of the first one is a major highway that can be ridden with a bicycle. What I'm wondering is this: if someone unfamiliar with the area got there and used a GPS unit to show those three roads, would the GPS unit show them the different gradients of the roads? Or is that another function that they'd need to download or otherwise install? Cheers My Garmin can display the current gradient and I have that in my main screen. There is also a page to show the upcoming elevations. Generally though I look at the route in RideWithGPS before hand to get a decent idea of what to expect from the elevation profile. -- duane |
#4
|
|||
|
|||
GPS Units = Show road steepness?
Ralph Barone wrote:
Sir Ridesalot wrote: Talking about GPS units on another thread reminded me of something else I wondered if they do. Does a bicycle GPS unit show you the steepness of roads? There's an area that I frequently ride where on road has short but very steep hills, another road a mile or so east of it has much more gradual hills whilst a third road to the west of the first one is a major highway that can be ridden with a bicycle. What I'm wondering is this: if someone unfamiliar with the area got there and used a GPS unit to show those three roads, would the GPS unit show them the different gradients of the roads? Or is that another function that they'd need to download or otherwise install? Cheers My Garmin 705 shows the slope as I ride it, and historically, but not preemptively. For that, I used Google Earth. The edge 800 has an elevation screen. -- duane |
#5
|
|||
|
|||
GPS Units = Show road steepness?
On 3/9/2019 4:46 PM, Sir Ridesalot wrote:
Talking about GPS units on another thread reminded me of something else I wondered if they do. Does a bicycle GPS unit show you the steepness of roads? There's an area that I frequently ride where on road has short but very steep hills, another road a mile or so east of it has much more gradual hills whilst a third road to the west of the first one is a major highway that can be ridden with a bicycle. What I'm wondering is this: if someone unfamiliar with the area got there and used a GPS unit to show those three roads, would the GPS unit show them the different gradients of the roads? Or is that another function that they'd need to download or otherwise install? Cheers As others have noted, many (all?) Garmin units can display gradient (as in "6% grade". As noted in another thread, GPS units are notoriously not very accurate in their altitude calculation, so the more expensive units have a barometric "backup". If you are using a pre-loaded course (e.g. a .TCX file) on your GPS, (?some? ?all? my!) Garmins can display the profile of the upcoming few miles. My own experience over 7 years with Garmin units (that have barometric "backup" to the altimeter calculation) is that the reported gradient is /fairly/ consistently reported (on many rides over the same hills), though the peak steepness will vary by a percent or so. Maybe that's 'cause I wasn't looking when the highest number was on the screen, or because the unit updated at different points on the road on different rides of the hill. Finally, if you use ridewithgps.com, and I assume any similar sites/software, note that gradient reporting there usually misses peak values, as the software tends to average over larger segments of the course. For example, on one local hill I ride a lot, the peak gradient appears to be about 12% for maybe 50-100 feet, as measured with both GPS and inclinometer. Ridewithgps.com reports a peak of 7.2%, which is probably true if you average over longer segments. Mark J. |
#6
|
|||
|
|||
GPS Units = Show road steepness?
On 3/10/2019 10:56 AM, Mark J. wrote:
On 3/9/2019 4:46 PM, Sir Ridesalot wrote: Talking about GPS units on another thread reminded me of something else I wondered if they do. Does a bicycle GPS unit show you the steepness of roads? There's an area that I frequently ride where on road has short but very steep hills, another road a mile or so east of it has much more gradual hills whilst a third road to the west of the first one is a major highway that can be ridden with a bicycle. What I'm wondering is this: if someone unfamiliar with the area got there and used a GPS unit to show those three roads, would the GPS unit show them the different gradients of the roads? Or is that another function that they'd need to download or otherwise install? Cheers As others have noted, many (all?) Garmin units can display gradient (as in "6% grade".Â* As noted in another thread, GPS units are notoriously not very accurate in their altitude calculation, so the more expensive units have a barometric "backup".Â* If you are using a pre-loaded course (e.g. a .TCX file) on your GPS, (?some? ?all? my!) Garmins can display the profile of the upcoming few miles. My own experience over 7 years with Garmin units (that have barometric "backup" to the altimeter calculation) is that the reported gradient is /fairly/ consistently reported (on many rides over the same hills), though the peak steepness will vary by a percent or so.Â* Maybe that's 'cause I wasn't looking when the highest number was on the screen, or because the unit updated at different points on the road on different rides of the hill. Finally, if you use ridewithgps.com, and I assume any similar sites/software, note that gradient reporting there usually misses peak values, as the software tends to average over larger segments of the course.Â* For example, on one local hill I ride a lot, the peak gradient appears to be about 12% for maybe 50-100 feet, as measured with both GPS and inclinometer.Â* Ridewithgps.com reports a peak of 7.2%, which is probably true if you average over longer segments. Mark J. Here's an article on the trickiness of measuring steepness: http://www.roberts-1.com/b/v/e/08a/i...ring_steepness |
#7
|
|||
|
|||
GPS Units = Show road steepness?
On Sunday, March 10, 2019 at 11:11:41 AM UTC-7, Bertrand wrote:
On 3/10/2019 10:56 AM, Mark J. wrote: On 3/9/2019 4:46 PM, Sir Ridesalot wrote: Talking about GPS units on another thread reminded me of something else I wondered if they do. Does a bicycle GPS unit show you the steepness of roads? There's an area that I frequently ride where on road has short but very steep hills, another road a mile or so east of it has much more gradual hills whilst a third road to the west of the first one is a major highway that can be ridden with a bicycle. What I'm wondering is this: if someone unfamiliar with the area got there and used a GPS unit to show those three roads, would the GPS unit show them the different gradients of the roads? Or is that another function that they'd need to download or otherwise install? Cheers As others have noted, many (all?) Garmin units can display gradient (as in "6% grade".Â* As noted in another thread, GPS units are notoriously not very accurate in their altitude calculation, so the more expensive units have a barometric "backup".Â* If you are using a pre-loaded course (e.g. a .TCX file) on your GPS, (?some? ?all? my!) Garmins can display the profile of the upcoming few miles. My own experience over 7 years with Garmin units (that have barometric "backup" to the altimeter calculation) is that the reported gradient is /fairly/ consistently reported (on many rides over the same hills), though the peak steepness will vary by a percent or so.Â* Maybe that's 'cause I wasn't looking when the highest number was on the screen, or because the unit updated at different points on the road on different rides of the hill. Finally, if you use ridewithgps.com, and I assume any similar sites/software, note that gradient reporting there usually misses peak values, as the software tends to average over larger segments of the course.Â* For example, on one local hill I ride a lot, the peak gradient appears to be about 12% for maybe 50-100 feet, as measured with both GPS and inclinometer.Â* Ridewithgps.com reports a peak of 7.2%, which is probably true if you average over longer segments. Mark J. Here's an article on the trickiness of measuring steepness: http://www.roberts-1.com/b/v/e/08a/i...ring_steepness Since the usual GPS satellites are well over the horizon, using them to get an accurate altitude reading is difficult at the very least. Also the news ones are pretty low altitude and moving really fast. This compounds the problem. So there has to be one hell of a lot of computation just to find your position let alone your altitude. Now let's make it more complicated - the MPU's use more energy the faster they operate so if you want your unit to last a long time and be reasonably compact AND do all of this computation you really have your hands full with just position let alone attempting to calculate altitude. The way I would first look into it would be to use a satellite as close to zenith as possible and use signal transit time to calculate altitude. |
#8
|
|||
|
|||
GPS Units = Show road steepness?
On Sunday, March 10, 2019 at 1:46:44 AM UTC+1, Sir Ridesalot wrote:
Talking about GPS units on another thread reminded me of something else I wondered if they do. Does a bicycle GPS unit show you the steepness of roads? There's an area that I frequently ride where on road has short but very steep hills, another road a mile or so east of it has much more gradual hills whilst a third road to the west of the first one is a major highway that can be ridden with a bicycle. What I'm wondering is this: if someone unfamiliar with the area got there and used a GPS unit to show those three roads, would the GPS unit show them the different gradients of the roads? Or is that another function that they'd need to download or otherwise install? Cheers GPS can show the actual gradient but it uses some sort of averaging algorithm which means it has a delay. This makes it pretty useless IMO. Besides this what are you gonna do if you know the exact gradient at that moment? GPS can tell you exactly were you are. For navigation you need a routable map and navigation software. Often people have a too high expectations of a GPS based cycling computer and end up never using the navigation capability and just have an expensive cycling computer or head unit as they are called now because speed sensors, cadence sensors, power meters, radar, lights, action camera's, HRM and your phone all connect to the unit and show their information on the head unit or can be operated using the head unit. Lou |
#9
|
|||
|
|||
GPS Units = Show road steepness?
Sir Ridesalot wrote:
Talking about GPS units on another thread reminded me of something else I wondered if they do. Does a bicycle GPS unit show you the steepness of roads? There's an area that I frequently ride where on road has short but very steep hills, another road a mile or so east of it has much more gradual hills whilst a third road to the west of the first one is a major highway that can be ridden with a bicycle. What I'm wondering is this: if someone unfamiliar with the area got there and used a GPS unit to show those three roads, would the GPS unit show them the different gradients of the roads? Or is that another function that they'd need to download or otherwise install? Cheers Various mapping sites will show the gradient, and some GPS units will show the gradient, in the same way that it can give improbable maximum speeds they can also give improbable max gradients or sometimes on very short ramps not notice it, there is a nasty little ramp nr my folks place, which is the software flattens claiming 12% when it’s a fair cruel 25/30% even more cruel this weekend with a 50mph headwind. Roger Merriman |
#10
|
|||
|
|||
GPS Units = Show road steepness?
On Sunday, March 10, 2019 at 9:38:46 PM UTC+1, wrote:
On Sunday, March 10, 2019 at 11:11:41 AM UTC-7, Bertrand wrote: On 3/10/2019 10:56 AM, Mark J. wrote: On 3/9/2019 4:46 PM, Sir Ridesalot wrote: Talking about GPS units on another thread reminded me of something else I wondered if they do. Does a bicycle GPS unit show you the steepness of roads? There's an area that I frequently ride where on road has short but very steep hills, another road a mile or so east of it has much more gradual hills whilst a third road to the west of the first one is a major highway that can be ridden with a bicycle. What I'm wondering is this: if someone unfamiliar with the area got there and used a GPS unit to show those three roads, would the GPS unit show them the different gradients of the roads? Or is that another function that they'd need to download or otherwise install? Cheers As others have noted, many (all?) Garmin units can display gradient (as in "6% grade".Â* As noted in another thread, GPS units are notoriously not very accurate in their altitude calculation, so the more expensive units have a barometric "backup".Â* If you are using a pre-loaded course (e.g. a .TCX file) on your GPS, (?some? ?all? my!) Garmins can display the profile of the upcoming few miles. My own experience over 7 years with Garmin units (that have barometric "backup" to the altimeter calculation) is that the reported gradient is /fairly/ consistently reported (on many rides over the same hills), though the peak steepness will vary by a percent or so.Â* Maybe that's 'cause I wasn't looking when the highest number was on the screen, or because the unit updated at different points on the road on different rides of the hill. Finally, if you use ridewithgps.com, and I assume any similar sites/software, note that gradient reporting there usually misses peak values, as the software tends to average over larger segments of the course.Â* For example, on one local hill I ride a lot, the peak gradient appears to be about 12% for maybe 50-100 feet, as measured with both GPS and inclinometer.Â* Ridewithgps.com reports a peak of 7.2%, which is probably true if you average over longer segments. Mark J. Here's an article on the trickiness of measuring steepness: http://www.roberts-1.com/b/v/e/08a/i...ring_steepness Since the usual GPS satellites are well over the horizon, using them to get an accurate altitude reading is difficult at the very least. Also the news ones are pretty low altitude and moving really fast. This compounds the problem. So there has to be one hell of a lot of computation just to find your position let alone your altitude. Now let's make it more complicated - the MPU's use more energy the faster they operate so if you want your unit to last a long time and be reasonably compact AND do all of this computation you really have your hands full with just position let alone attempting to calculate altitude. The way I would first look into it would be to use a satellite as close to zenith as possible and use signal transit time to calculate altitude. For every position on earth the altitude is known (measured during a Space shuttle mission if I recall correctly). The information is available for free. I use it to correct the altitude measurements of my rides afterwards. It should be possible for a GPS unit to show the altitude based on the measured position instead of trying to calculate it or measuring it with a barometer. Lou |
Thread Tools | |
Display Modes | |
|
|
Similar Threads | ||||
Thread | Thread Starter | Forum | Replies | Last Post |
Pothole gardener stars on Road Rage TV show | Alycidon | UK | 0 | February 10th 16 01:12 PM |
Show off now faces arrest after road damage | Alycidon | UK | 5 | October 5th 15 11:00 PM |
gps units | recycled[_2_] | General | 1 | July 26th 09 11:59 PM |
FS: 2 Polar Power units | Andre | Marketplace | 0 | June 17th 05 12:13 AM |
FS: 2 polar power units | Andre | Marketplace | 0 | June 11th 05 10:49 PM |